( ex1)

#include<iostream.h>
#include<string.h>
#include<fstream.h>
#include<stdlib.h>
void main()
{char s[50],*p,s1[50],s2[50];
int k,sum=0,x;
fstream f("date.in",ios::in);
fstream g("date.out",ios::out);
f>>s;
strcpy(s2,s); copie a sirului initial
strcat(s,"+");
g<<s2;
p=strchr(s,'+');
while(p)
{x=p-s;
strxfrm(s1,s,x+1); extrag numarul din fata semnului+
k=atoi(s1);// conversia stringului intr-un numar
sum=sum+k;
strcpy(s,p+1);
p=strchr(s,'+');
}
g<<"="<<sum;

}